(More on texts, since the weather isn’t letting me do anything outside)
Is that they get re-written and edited. An annoying example I have just worked out is the ‘Compound of Compounds’, (or Compositum de Compositis in the original latin) frequently attributed to Albertus Magnus.
The earliest copy claims to have been written in Paris in 1331, and certainly everything about it matches that claim, which occurs in the rubrication (the bit written in red; medieval scribes did that to highlight important things or the start or end of a text) at the end of the work. No mention is made of Albertus Magnus, although one sentence says “For it is proved in our book on minerals that the generation of metals is circular”, and Albertus Magnus did indeed write a book about minerals, which is perhaps where later alchemists got the idea of it being written by him.

Now, an English translation was made for and published by Adam Maclean a decade ago. I bought it 3 or 4 years ago, and was enamoured of the long sequence of dissolutions given in chapter 5 onwards. These involved the distillation of acids and the dissolution of mercury and other metals in them. The first 3 chapters are the usual sort of high medieval introduction to what metals are made of and the importance of sulphur, mercury and arsenic for making an elixir.

However something always worried me about the text as a whole. The practical bits about distillation of mineral acids and their use to dissolve mercury to make the first matter, i.e. the mercury has been reduced to a mixture of the first level of material, below the four elements, whereupon it can have imprinted upon it the balance of elements needed to make gold or silver, always seemed different from the first 3 chapters. They were too practical in a modern sort of way, didn’t mention arsenic and felt wrong, not early 14th century at all. Maybe that was an artefact of having been translated twice, I thought.

So before carrying out such experiments, I determined to compare the English translation to the original text, which is held in the National Library of Scotland.
Finally, after a number of hours work, the medieval handwriting, a Gothic sort of script, became more legible and I was able to compare the original MS with the translation. (Someone else was also there studying it too, but I never met them and they haven’t responded to my request for email)
But what I found was extremely vexing.

The original mentions lead, tin and repeated washings with sal-ammoniac and other liquids. Tin and lead are not mentioned in the modern version. The modern version, although following the original in the first 3 chapters, appeared just a bit more complexly written, but my impression may be faulty due to my poor understanding of Latin. In both texts in the first 3 chapters there were quotations from Geber and Rhazi and a similar understanding of the principles within substances, such as sulphur having 3 moist principles in it.

Then I got to chapter 4, and the texts really seemed to diverge.
The handwriting in the MS got a bit worse as well, but what I could make out was that the original MS carried on with the work in pseudo-Rhazi like fashion, using and producing oils of various sorts and using metal calxes. Thorndike’s notes on it agree with me and mention the use of vinegar, sour milk, urine of boys, and lye.
Chapter 3 in the translation has a section which says to make the blood of roman vitriol using salteptre and roman vitriol i.e. iron sulphate, but Thorndike makes no mention of it and this seemed a bit too clear for making a mineral acid in the early 14th century.

Chapter 4 is where it really goes off the rails, the translation telling how to make mercuric chloride using salt, roman vitriol and mercury. This is not a new process, it goes back to IIRC the 12th century or so and was possibly invented in Spain by Arabic alchemists. But this recipe was not in the original.

At this point I was disturbed, the translation wasn’t what it was supposed to be, the Compound of Compounds.
So I have carried out a little more research, and it turns out that I was correct.
First I had to determine from where came the French text that was translated into English. This took a while, including asking Adam Maclean where the French original had come from, but it turned out to be based on the Latin of the Compound of Compounds that was printed in Volume 4 of Lazarus Zetzner’s “Theatrum Chemicum”, printed in Strasbourg in 1613, a well known compendium of alchemical texts.

Fortunately that is available online thanks to the work of Rafal Prinke and others. So I found immediately that it had the different 4th chapter onwards. But what were the manuscripts like?

I found more information quite quickly (Search engines covered this area better than I expected). Pearl Kibre, in the paper “Alchemical writings attributed to Albertus Magnus” notes that the text was attributed to Albertus Magnus in the 15th century, and that the Zetzner printed edition deviates from the manuscripts after the third section.

Or in other words, at some point prior to 1613, a cut and shut job was carried out on the text. The first 3 original 1331 chapters were copied out and bolted onto a later series of recipes and a new start and end paragraphs added.

But when???
I can’t be sure, but from the confidence with which mineral acids are made and discussed (It even says that one of them will turn the skin of a man orange, which I know nitric acid does because I’ve had orange skin from it myself), I am sure that it is late medieval or 16th century. By the 16th century knowledge and use of the mineral acids was widespread amongst alchemists, miners and others. So someone came up with a rather original alchemical path, but wanted to boost its popularity by stealing the name and fame of Albertus Magnus.

Maybe there’s an original manuscript of it somewhere, that would be really good, but I doubt it, not if it hasn’t come to light by now. Greater knowledge of the early use of mineral acids and better dating of their use would be of value in the history of chemistry and our understanding of their use. But such investigations are made more difficult by the lack of good editions or translations of the various texts.

In this case, it might be worth trying to locate antecedents of the recipes for acids given in the text. Some general work has been done on the history of specific alchemical substances, much less on specific recipes. There is a great deal more work to be done on alchemical apparatus, chemicals and laboratory practise, and I would like to contribute what I can.

After I had written the above I managed to find yet another paper on the history of nitric acid (By Karpenko) and it gave me some new leads, such as it being mentioned in the Rosarius Minor by Arnold of Villanova and one of Rupescissa’s works, as well as The book of the holy Trinity, an early 15th century German work. In the latter it is called aqua fortis, that is, strong water, and it also has a great deal of alchemical symbolism in images that accompany the text. As the author notes, this sort of thing indicates that the mineral acids originated in the alchemical laboratory and moved into the artisanal one; it was used for parting gold and silver, and of course a lot of goldsmiths were interested in alchemy.

So the date for the earliest use of mineral acids is around the time that the original MS of the Compound of Compounds was written, but the author had not heard of them or was not interested in using them, which is amusing. I wonder how rapidly the recipes spread across Europe in the 14th century? Did alchemists write letters or travel and copy texts? Did the prohibitions against the practise of alchemy made by all the monastic orders and friars as well as by Pope John 22nd retard the transfer of new recipes? Or maybe the black death did that later in the century, just as knowledge of mineral acids was getting ready to spread across the continent, following the trail blazed by knowledge of distillation of spirits of wine.
Either way, it appears to me so far that mineral acids didn’t really become fully integrated until the 15th century and after, which is interesting enough in itself.